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When to Plant Pumpkin in Colby, Wisconsin (54421)

Location

Colby, Wisconsin

ZIP Code

54421

USDA Zone

4b

Last Frost

Tuesday, May 5, 2026

📅 Planting Calendar

Direct Sow Outdoors Tuesday, March 24, 2026

Pro Tip: Sow Pumpkin directly outdoors 6 weeks before your last frost date.

🌿 Plant Details

Scientific Name Cucurbita maxima
Days to Maturity 100 days
Mature Height 12-24"
Spread 120"
Type Vine
Fruit Size Large (8-20 lbs)

☀️ Growing Requirements

☀️

Sun

Full Sun (6-8 hours)

💧

Water

Regular (1 inch/week)

↔️

Spacing

60" apart

🌱

Planting Depth

1" deep

Seeds typically germinate in 5-10 days

Ready to Plant Pumpkin in Colby?

Get your seeds now so they're ready by Tuesday, March 24, 2026.

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🤝 Good Companions

CornBeanMarigoldNasturtium

⚠️ Avoid Planting Near

Potato

Other Plants for Colby

Growing Pumpkin in Zone 4b

Pumpkin (Cucurbita maxima) is a popular garden vegetable. In Colby, Wisconsin, which is in USDA Hardiness Zone 4b, you should direct sow seeds around Tuesday, March 24, 2026.

Your average last frost date is Tuesday, May 5, 2026. Pumpkin grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.